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Technical environment
Technical environment
Global standard 220V-240V/50Hz-60Hz
Standard for USA/Canada 120V/60Hz, 277V/60Hz
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Colour rendition

The quality of how colors are reproduced is called color rendering. Line spectra have very good color rendering. Line spectra allow only a single color to be perceived well. Multi-line spectra render several colors of the respective spectrum well, but color rendering is weaker in the intermediate ranges. Blue and green colors appear comparatively gray and dull in warm white incandescent light despite excellent color rendering. However, these color tones appear clear and luminous in the light of daylight white fluorescent lamps – despite poorer color rendering. With the rendering of yellow and red color tones, this phenomenon of weakening or intensifying of the color effect is reversed.

Because the eye is able to adapt to light of the most different color temperatures, the color rendition must be determined dependent on the color temperature. Tungsten halogen lamps feature very good color rendition. The rendition quality of fluorescent lamps and metal halide lamps ranges from good to average. The degree of color distortion against a reference light source is indicated using the color rendition index Ra or the color rendition grading system. The color rendition index is only used for white colors of light.

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Colour rendition Colour rendition
Colour rendition

The same colours of light can produce a different rendition of a body colour due to different spectral constitution. Continuous spectra lead to a unifrom colour rendition. Linear spectra only correctly render a very small colour range. Multiline spectra are compiled from different linear spectra and thus improve the colour rendition. The more spectra can be bound to one linear progression, the better the colour rendition. Incandescent lamps feature a linear spectrum, while discharge lamps have a multiline spectrum.

Colour rendition

Very good colour rendition is important for
  • exhibitions
  • trade-fair stands
  • sales rooms
  • offices
  • workstations

Colour rendition

Colour rendition refers to the quality of the reproduction of colours under a given illumination. The degree of colour distortion is indicated using the colour rendition index Ra and/or the colour rendition grading system. A comparative light source with continuous spectrum serves as a reference light source, whether this be a temperature radiator of comparable colour temperature or the daylight.

Colour rendition

To enable the color rendition of a light source to be determined, the chromatic effects of a scale of eight body colors viewed under the type of illumination being scrutinized and also under the reference illumination are calculated and related to each other. The resulting quality of color rendition is expressed in color rendition indices; these can relate both to the general color rendition (Ra) as an average value or to the rendition of individual colors. The maximum index of 100 signifies ideal color rendition as experienced with incandescent lamp light or daylight. Lower values refer to a correspondingly worse color rendition. Linear spectra of light lead to good color rendition. Linear spectra in general lead to a worse rendition. Multiline spectra are composed of several different linear spectra and improve the color rendition.

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